Preparatory level——Level0——Level1—-Level2—-Level3—-Level4—-Level5—-Level6—-Level7—-Level8—-Level9—-Level10—-Level11—-Level12—-Level16. 最重要的是Preparatory Level—-Level0, 以及Level0—-Level1。 从Level1往上，基本就要看天赋了。
Preparatory level——Level0——Level1—-Level2—-Level3—-Level4—-Level5—-Level6—-Level7—-Level8—-Level9—-Level10—-Level11—-Level12—-Level16. 最重要的是Preparatory Level—-Level0, 以及Level0—-Level1。 从Level1往上，基本就要看天赋了。